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Understanding citizen environmental perception is a crucial issue to improve outdoor environmental and landscape quality. This paper is aimed at investigating the perspective of travelling citizens about local microclimate conditions in a transportation open-air hub of an urban district in central Italy, to propose effective mitigation strategies. Therefore, a survey was submitted to pedestrians while crossing the area to understand their actual perception of visual-thermal-acoustic conditions characterizing the outdoor environment, with varying weather and personal characteristics. Simultaneously, the continuous in-situ monitoring of the main environmental parameters was performed. Finally, the benefits generated by selected microclimate mitigation and landscape improvement strategies were quantitatively assessed by means of validated microclimate district models. Results of the field survey highlighted the minor tolerance of the local environment by local citizens compared to tourists, especially those coming from denser and more polluted cities. Moreover, the simulations confirmed the capability of selected microclimate mitigation strategies against anthropogenic heat, to improve pedestrians’ outdoor thermal comfort conditions in summer, without winter penalties. In particular, the vegetation increase, according to pedestrians’ request for additional green areas, combined to other solutions for sustainable landscape change, showed the most significant impact in summer overheating mitigation and urban resilience to anthropogenic climate change. [ABSTRACT FROM AUTHOR]

Natural and bio-based construction materials represent a promising solution for optimizing buildings' environmental sustainability. In this view, the paper presents the multipurpose experimental thermo-acoustic characterization of common reed-based building panels. Different geometries, densities, humidity rates and stalk shapes were considered and tested by means of hot-plate, hot-box and impedance tube in-lab experimental benches. The thermal analysis showed that the geometry scarcely affects the thermal conductivity, which is around 0.05 W/mK and, therefore, comparable to other materials already commercialized for the same scope. On the other hand, the acoustic behavior is strongly affected by the stalk configuration, e.g. perpendicular, parallel or combined orientation with respect to the incident wave. In particular, the longitudinal stalk layout showed a significant sound ​absorption performance. The exhaustive experimental original characterization of such by-product, therefore, showed a very promising overall thermo-acoustic behavior. At the same time, for optimizing the panel field performance, the acoustic requirements should represent the panel design drivers, given the high sensitivity of the panel layout characteristics affecting the acoustic performance. [ABSTRACT FROM AUTHOR]

Recently, research focused on the development of roofing and paving systems aimed at (i) enhancing the passive cooling at single-building level and (ii) mitigating urban heat island at inter-building scale. In this work, the optic-thermal behavior of a naturally cool gravel for roof and paving application is studied, through lab and field experimental analyses. Specific evaluation about the cooling potential is carried out with varying grain size of the same gravel and stone typology. Additionally, its cool roof effect is investigated through dynamic simulation in a case study university campus in Italy. Finally, the analysis of the global warming contribution of the gravel was performed, with reference to the most performing gravel size. The results show differences up to 24% in terms of albedo with varying the only grain size. Additionally, the gravel with the smallest grain size resulted the most performing in terms of summer energy saving and indoor thermal comfort. By shifting from single building scale models to global climate energy balance models, an equivalent carbon emission offset of 4400 tCO 2eq was found, imputable to the (i) energy saving contribution, and (ii) global warming mitigation effect produced by the enhanced albedo of the case study area. [ABSTRACT FROM AUTHOR]

A gasification plant was designed and built to test syngas production from biomass for electricity generation on microscale. The plant is mainly composed by a downdraft reactor, a gas cleaning section with a cyclone and a wet scrubber, a blower for syngas extraction and an ICE (Internal Combustion Engine, Lombardini LGA 340), equipped with an alternator. A small quantity of producer was also eventually sent to a button cell SOFC (Solid Oxide Fuel Cell) for preliminary characterization. The plant was tested in a preliminary experimental campaign to evaluate mass and energy balances and process efficiency. Woody biomass was used and the producer gas firstly passed through impingers bottles, to condense and measure tar concentration (according to CEN/TS 15439), and then the remaining uncondensed gas was analyzed with a micro-GC (Gas Chromatograph). The paper presents and discusses the results of the preliminary tests carried out. [ABSTRACT FROM AUTHOR]

The world-wide effort to reduce the environmental impact associated to the industrial sector is quickly producing an increasing feedback on national and international decision makers. In this context, the analysis of life-cycle based assessments on the main impact categories associated to the pre-production, production, assembly, use, and end-of- life phases represents a powerful tool towards a holistic interpretation of the footprint from industrial buildings. The Italian prefabricated building sector, characterized, on average, by local enterprises with regional coverage, has been investigated in order to study the Carbon and Energy Footprints. Data from a large company, running several facilities spread on the national territory, have been collected and analyzed in order to provide a parameterized evaluation of the GHG emission and the energy consumption associated to the single phases of the building life cycle as a function of the sensible design requirements. The quantification of the Carbon and the Energy footprint, associated to the prefabricated industrial building sector, is presented. The assessment procedure is performed through a parametric modeling of the building properties bases on the analysis of different sizes and designs. A detailed discussion of the outputs is presented, including the comparison of the environmental performance depending on different construction requirements. [ABSTRACT FROM AUTHOR]

Abstract: Starting from a numerical simulation of tropical atmosphere in radiative convective equilibrium a perturbation to the surface condition has been applied and the subsequent adjustment of the atmosphere has been analyzed. 3D data have been averaged in space and time using as energy variable to sort them the moist static energy, that is conserved for a moist atmosphere during adiabatic fluid parcel displacements. Since the energy balance of the system corresponds to vertically averaged terms of the MSE differential budget, a entropy derived variable- corresponding to a total thermodynamic energy variable- the θe equivalent potential temperature, has been analyzed using the vertically block averaged column data sorted by MSE. A close correlation between the energy distribution analyzed as quartile and mean for the θe and RH vertical profiles is found, highlighting the dynamical link existing between energy and moisture/heat statistical distribution of the system. [Copyright &y& Elsevier]

Abstract: A numerical simulation of tropical atmosphere in radiative convective equilibrium has been carried out and water data in different phases have been analyzed. 3D data have been averaged in space and time using as energy variable to sort them the moist static energy, that is conserved for a moist atmosphere during adiabatic fluid parcel displacements. The block averaged MSE gives a measure of the moisture flux that is dominating at statistical equilibrium triggering strong convection. MSE block vertical integrals, that give a measure of humidity going from dry to moist columns, are used to sort block integrals of variables. If the distribution of rainfall and precipitable water is analyzed using this technique, a correspondence between the moisture flux and total precipitable water (TPW) variability is found. The associated aggregation of precipitation rate is analyzed and different statistical behavior of moist and dry regions of the atmosphere is found. [Copyright &y& Elsevier]

Abstract: Glazing systems have an important role in buildings. Many studies show that health, comfort and productivity are improved thanks to the contribution of natural light. The aim of the present paper is to evaluate the thermal comfort indexes and the energetic performance of a lecture room in unsteady-state conditions. The research is addressed to non-residential buildings and it consists of two parts: experimental investigation and numerical analysis. Experimental campaigns were carried out in a lecture room of the Faculty of Engineering at the University of Perugia. Several parameters were measured: indoor and outdoor air temperature, solar radiation, surface temperature of external walls, glasses and frames, etc. The thermal comfort indexes (such as Predicted Mean Vote, PMV, and Predicted Percentage of Dissatisfied, PPD) were calculated. The simulations of the thermal behaviour of the tested room were performed using both ENERGYPLUS and TRNSYS softwares. Simulation models were tested and validated with experimental data; a new weather database was compiled for Perugia, by using the measured hourly data for air temperature, solar radiation and relative humidity. The analysis allowed to compare some different scenarios (glazing types and building orientation) in terms of thermal comfort indexes and energy demand. [Copyright &y& Elsevier]